Fix yarn install and building steps, otherwise they failed when you start from scratch

[damianavila]

Some things I was surprised about...

1. After doing the yarn install, all the JS on rise-reveal was "moved" from node_modules into the export directory.
   Since we are using cp -r, I was surprised to find the node_modules inside rise-reveal empty...

2. I guess the images from the chalkboard and the html file from the notes need to be copied over explicitly because they are not JS/CSS files, correct?

Again, thanks for working on this port!!

[fcollonval]

Thanks a lot for taking the time to review this big piece...

1. After doing the yarn install, all the JS on rise-reveal was "moved" from node_modules into the export directory.
   Since we are using cp -r, I was surprised to find the node_modules inside rise-reveal empty...

This is a side effect of using lerna and yarn workspace - all dependencies of all packages are pulled in at top node_modules to reduce the download size and to try using the same dependencies version for all packages.

2. I guess the images from the chalkboard and the html file from the notes need to be copied over explicitly because they are not JS/CSS files, correct?

This is a side effect of webpack (mandatory for JLab). It packages the code by keeping only what is explicitly mentioned. As reveal.js plugins contain static files it can be complex to tell webpack what additional files need to be included. So I went for a simple way by copying them where lab-like apps can find them.

[damianavila]

Thanks for the clarifications, @fcollonval!! And for the merge 😉!